stasis

(485 to 444 mya) We are told: From ScienceDaily: Spectacular Moroccan fossils redefine evolutionary timelines Some of the oldest marine animals on the planet, including armoured worm-like forms and giant, lobster like sea creatures, survived millions of years longer than previously thought, according to a spectacularly preserved fossil formation from southeastern Morocco. ‘Horseshoe crabs, for example, turn out to be at least 20 million years older than we thought. The formation demonstrates how important exceptionally preserved fossils are to our understanding of major evolutionary events in deep time’ says Peter Van Roy, also of Yale, who first recognised the scientific importance of the Fezouata fauna and is lead author of the study, part of a project funded by the National Read More ›

From ScienceDaily: Research conducted in Okinawa, Japan, by graduate student Yu Miyazaki and associate professor James Davis Reimer from the University of the Ryukyus has found a very unusual new species of octocoral from a shallow coral reef in Okinawa, Japan. The new species can be considered a “living fossil,” and is related in many ways to the unusual blue coral. More. The blue coral apparently dates from the Cretaceous period. Note: Some of us think that the term “living fossil” should be replaced by durable species: We human beings aren’t “living fossils” just because someone can dig up the bones of our ancestors and find out that they looked and lived a lot like us! So what is the Read More ›

Jaws were also more complex than expected. From ScienceDaily: A tiny tooth plate of the 410 million year old fossil fish Romundina stellina indicates that teeth evolved earlier in the tree of life than recently thought. That is a while back. The tooth plate of just some millimeters in size had been in a box for more than 40 years, without being recognized after the discovery and preparation of the fish it belonged to. Because no one expected to find anything like that. And few had any special desire to Everyone knows evolution is a long, slow process of natural selection acting on random mutation (Darwinian evolution). Every third rate biology teacher teaches that, and so do first raters, because Read More ›

The following post was generated by UD’s just-acquired, state-of-the-art news reporting app, Earlier Than Thought TM 😉 From the BBC: Scientists in China have described a new species of early bird, from two fossils with intact plumage dating to 130 million years ago. Based on the age of the surrounding rocks, this is the earliest known member of the clade that produced today’s birds: Ornithuromorpha. It pushes back the branching-out of this evolutionary group by at least five million years. … The little bird appears to have been a wader, capable of nimble flight. … previously the earliest known Ornithuromorph was 125 million years old. More. Here’s the abstract: Ornithuromorpha is the most inclusive clade containing extant birds but not the Read More ›

Here: The new fossil is the only record of an adult female insect from the Mesozoic, an era that spanned roughly 180 million years. The Mesozoic era was the age of the reptiles and saw both the rise and fall of the dinosaurs, as well as the breakup of the supercontinent Pangaea. The female ensign scale insect is preserved in a piece of amber retrieved from a mine in northern Myanmar (Burma). The specimen was trapped while carrying around 60 eggs and her first freshly hatched nymphs. The eggs and nymphs are encased in a wax-coated egg sac on the abdomen. This primitive form of brood care protects young nymphs from wet and dry conditions and from natural enemies until Read More ›

How does a life form that is still around get to be called a fossil at all? On what terms exactly? We human beings aren’t “living fossils” just because someone can dig up the bones of our ancestors and find out that they looked and lived a lot like us! So what is the term really doing in science anyway? Well, anyway, at Nautilus: The idea that some species are relics that have stopped evolving is finally going extinct. … Charles Darwin coined the term “living fossil” in The Origin of Species to describe some of the planet’s more ambiguous creatures—such as the lungfish and platypus—that evolved relatively early and “endured to the present day.” He saw these animals as Read More ›

Here: “I think the term ‘living fossil’ should be retired,” Turner says. “It does little good because it is almost always based on oversimplifications. ‘Living fossils’ often are judged based on some notion of overall morphological similarity. That was the case with crocs. If you squint, these various lineages all sort of look the same, but the details are all different. It ignores how evolution works on multiple levels. I wouldn’t miss it.” Oaks echoes him: “Overall, I think the term hurts more than it helps people’s understanding of evolution. Just because a species looks similar to fossils from many millions of years ago certainly does not mean that it has not evolved. The term ‘living fossil’ is often used Read More ›

From ScienceDaily: Arthropods (they of a hard outer-skeleton, like crustaceans, spiders, and insects) very often have larval phases that are completely different from the adults — such as caterpillars and butterflies. Allegedly, one of the reasons crabs have been so successful is that their larval life habits (diet, locomotion, etc.) are decoupled from their adult life habits. Most ancient fossils display a suite of “primitive” features, consistent with their early evolution and allowing them to be distinguished from their modern descendants. But the fossil described in this paper, despite its age, possesses a very modern morphology, indistinguishable from many crab larvae living today. “It’s amazing, but if we did not know this was a 150-million-year-old fossil, we might think that Read More ›